Fascination About impedance analyzer

Learnto usean impedancemeasurer!The fundamental measurement techniques

Overview

Impedance metersmeasure impedance,which is the resistance ofanAC.(AC). Thispage is a completeoutline of the fundamentals ofimpedance and methods of measuringimpedance, as well as howyou can use an impedance measurer.

What isimpedance?

Let’s begin by definingimpedance. Insimple words, impedanceisa measurement ofresistance to theflowthat isone’sAC current.

When you connect your electricproduct, motororany otherequipment toor from anACenergy source,the current flowsthrough thecircuitry of the device. Impedance isdeterminedthrough the division of the voltage inthe circuit byits current. Insimple terms, it canbedescribed as limiting theflow of currentwithinanAC circuit. Impedance isidentified byusing thesymbol “Z” and measured inthe ohms(O) this is the exactunit used to measureDC resistance. Thehigher the impedancethegreater resistance is thereto thecurrent flow.

How do you measure impedance?

As impedance itself isn’tvisible, it’snecessary to use a measuringinstrumentto gaugeit. Instrumentsthat can measureimpedance can include impedance analyzers,LCR meters as well as impedance analyzer. There area number ofmethods in which impedance canbe measured.

Bridge method

Thistechnique employsthe bridge circuit to calculateanunknownresistance. It requiresbalance adjustment tobeperformed using a galvanometer.Although the technique providesthe highest degree of accuracy(about 0.1 percent) It’s not the best suitedto high-speed measurement.

I-V method

This methodcalculates impedance usingthe voltagesthat cross a currentdetection resistor , and an unknownimpedance. Itis also usedto testsamplesin which the sample is grounded.As the impedance rises,themethod becomes more susceptibletothe effects ofthevoltage gauge.

Method RF I-V

This method usesthe samebasic measurement conceptthat is used in the I-V method. Itpermits high-frequency impedance measurementsthrough a circuit thatmatches the characteristic impedancea high-frequency coaxial cable andan high-frequency coaxial connector.It’s difficult to use thismethod to measure widebands becausethefrequency range used for measurementisrestrictedby the test head’s transformer.

Automatically balancedbridges

This method is based on the samefundamental measurement principles asthat of the bridge approach. Itcoversan extensive frequency range(11 mHz to 100 MHz).However, the coveragedoes not extend to highfrequencies.A large number ofLCR metersuse this technique.

Each impedance analyzer approach has its ownadvantages and disadvantages, soit is essential to knowthe kind of impedancesyou’ll needbefore deciding on the bestmethod to apply.

Utilizing an impedance meter

The methodused to measure the impedanceis dependent on the instrumentused.For example, Hioki’s LCMeter IM3523measures impedanceat a high level ofaccuracy in a varietyoffrequency settings.

• 40 Hz measurement

• 200measured Hz

Alongside normal measurements This instrument can be used tocontinuously and swiftly measure variousparametersin differentcircumstances(measurement frequency andthe signal level).

• C-D+ESR Measurement of Capacitors

impedance analyzeralso allows for the saving ofthe equivalent of 60 setsof measurement conditionor up-to128value of corrections for open/shortandlength correction.A set of settings can bequickly loadedto improve workefficiency.

In addition, the instrument’s exteriorcontrol terminalslet you buildautomatedtesting lines faster.

The causes of instability in impedancemeasurement

The measurement methodused, impedance meterscan return a different numberevery time a measurement ismade. Ifthemeasurement results do not seem to be stable make sure you check the following factors:

Components with parasitic characteristics of components that are beingmeasured

Alongside the designvaluesfor reactance and resistancecomponentscontain parasitic components thatcan cause a variance in measuredvalues.Variations in thelength ofthe leads that are connectedtothe components and thedistance between themcouldresult in measurements that differ.

Measurementenvironmental

The Impedance measurement results areaffected by manyconditions, includingvariations in temperature notjustresistorsbut also inductors and capacitors as well asprobe capacitance as well as stray capacitance.

Thisrequires stepsincluding maintaining a stablemeasurement space and averaging severalmeasurements instead ofusing onemeasurement tocalculatetheamount.

DC bias

DC biasis aminusculevoltage that can be found in measurementdevicesand circuits.For example, it occurswhen wires and probesaremade from different substances. Thethermal electromotive force that resultscreatesDC bias.

Summary

The Impedance measure the resistance ofan AC current, and itsmeasurement requiresa dedicated instrument.As there are a numberofmeasurement methods so it’s essential to pickthemost appropriate method based onthe purpose of your measurement and also each method’sadvantages anddisadvantages.

Impedance measurement is verydelicate and prone to variabilitydue to factors includingthe measurement environment, frequency as well asDC bias. Thischaracteristic necessitatesmethods like averaging of multiplemeasurements.

Applications

• Smart key/immobilizer antenna impedance measurements

• MLCC

• Conductive polymer capacitors

• Tantalum capacitors

How to Use

• LCRMeter measurement principles

• How to Use an LCR Meter: Basic Knowledge